Tuner says car is lean
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Tuner says car is lean
i sent a file to diablosport because one of the guys were gonna tune it for me and send me the tune file via email ya da ya da. The guy gets back to me telling me im runnin way lean and i cant figure out why because it doesn't sound lean. No vacuum leaks that i know of, and idle sounds good to me.
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Joined: Aug 2022
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From: Ashburn, VA
i sent a file to diablosport because one of the guys were gonna tune it for me and send me the tune file via email ya da ya da. The guy gets back to me telling me I'm running way lean and i cant figure out why because it doesn't sound lean. No vacuum leaks that i know of, and idle sounds good to me.
Typically you can smell a really lean car but even that's flawed. Albeit i'm kind of confused...isn't the job of a tuner [even mail-to-order] to tune the car 
If it's lean MF'er...add some fuel to the got damm map lol. Maybe he was looking at the fuel trim levels and deduced this. If it were me...I'd find a local tuner...get the car over there...and see what going on with the car. To say that the car is running too lean leaves to many variables...is it stock? Mod'ed? already have a custom tune? It's lean in comparison to what? Its like when people say a car is running warm...ok...how warm? 230 to some is to hot lolJoe
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Joined: Apr 2018
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From: Montgomery City, MO
You should probably go into specifics of what this file contained.
There's not much a tuner will be able to tell you about actual fuel mixture from a datalog unless you were logging with a wideband in both closed loop and PE mode (open loop).
Skewed trim #s can indicate a vacuum leak, a faulty or dirty MAF, but among other things they can also indicate the owner runs fuel with added ethanol (pretty much all gas contains at least 10% these days).
There's not much a tuner will be able to tell you about actual fuel mixture from a datalog unless you were logging with a wideband in both closed loop and PE mode (open loop).
Skewed trim #s can indicate a vacuum leak, a faulty or dirty MAF, but among other things they can also indicate the owner runs fuel with added ethanol (pretty much all gas contains at least 10% these days).
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From: Anthony TX
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St. Jude Donor '08
Joe,, I love your justified sarcasm! LMAO! All kidding aside, Joe is spot on. So is RonSSNova! You could also have a slight exhaust leak introducing air into the exhaust stream. Tooo many variables to consider! Bite the bullet, save the cash and have it tuned locally where you can watch, ask questions and work with the tuner.
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Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Again, As spfautsch stated,,, too many variables to make a logical conclusion on whats causing the issue.
The computer can only correct an out of trim condition to + or - 25% from zero fuel trim. Get a good live data scanner and look at your fuel trim data, O2 sensor data, actual engine sensor output data. . See what your LTFT is reading and if it sewed lean or rich, correct that root cause before trying to have your PCM tuned with a poorly running engine.
The computer can only correct an out of trim condition to + or - 25% from zero fuel trim. Get a good live data scanner and look at your fuel trim data, O2 sensor data, actual engine sensor output data. . See what your LTFT is reading and if it sewed lean or rich, correct that root cause before trying to have your PCM tuned with a poorly running engine.
